Pattern-drawing apparatus.



H. P. MACDONALD. PATTERN DRAWING APPARATUS.

APPLIGATION FILED mm 2s, 1.913.

Patented Feb. 24, 1914.

WITNESSES Airs ATENT oFFioE.

HARRY P. MACDONALD, OF MONTCLAIR, NEW JERSEY, ASSIGNOR TO THE SNEAD & CO. IRON WORKS, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.

PATTERN-DRAWING APPARATUS.

Specification of Letters Patent.

Patented Feb. 24, 1914.

1/ b all whom it may concern:

Be it known that I, HARRY P. MACDONALD, a citizen of the United States, residing at Montclair, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Pattern-Drawing Apparatus, of which the following is a specification.

This invention relates to sand molding apparatus, and has reference particularly to an improved form of pattern drawing mechanism which is simple and inexpensive in construction, and effective in operation.

My invention further contemplates the provision of improved means for supporting the pattern table during the ramming of the mold; and the provision of an improved arrangement of operating mechanism for raising and lowering the pattern table.

Other objects of the invention reside in the provision of improved means for preventing sand, dust and dirt from having access to the operating mechanism, and of improved means for lubricating the operating mechanism. 1

The foregoing, together with such other objects as may hereinafter appear or are incident to the invention, I attain by means of a structure which I have illustrated in preferred form in the accompanying drawings, wherein Figure 1 is a plan view of my improved apparatus with the pattern table removed; Fig. 2 is an irregular section on the line ITII of Fig. 1; Fig. 3 is a section through one of the operating shafts and illustrates the method of lubricating the parts; Fig. 4 is a plan view of a detail of my invention; and Figure 5 is an end elevation of a detail of my invention.

Referring now to the drawings, it will be seen that my apparatus comprises a main frame 7 preferably made of cast iron, which frame is open at the ends and provided with side walls 8 which extend upwardly. The ends of the frame are partially closed by means of the cast end pieces 9 which extend between the side walls. The pattern table 10 fits snugly between the side walls of the frame and can be readily raised and lowered, the operating mechanism for raising and lowering the table being of the toggle type, as will further appearv Secured to each end of the pattern table is a downwardly depending end plate 11, said plates abutting against the exterior faces of the end pieces 9 of the frame work. It will be seen from the fore-going that the framework and the pattern table together with the end plates 11 constitute an inclosed box in which the operating mechanism is mounted. The operating mechanism comprises the toggles 12 which are arranged in pairs at opposite ends of the apparatus; the segmental gears 18 which are likewise arranged in pairs adjacent the central portion of the apparatus; the links 14 which connect the gears and the toggles; the rock shafts l5 and 16 to which the gears 13 are keyed;'and the operating lever 17 keyed to the rock shaft 15. The rock shafts 15 and 16 have bearings in the side walls and in a saddle plate or bearing 18 carried on the block 19 which is secured to the central portion of the'main frame 7. The pattern table is adjustably carried on the toggles 12 by-means of the adjustable connections 20 which are of the type illustrated inv my co-pending application Ser. No. 7 38,694, filed Dec. 26, 1912. It will be clear from inspection of Fig. 2 that the pairs of segmental gears intermesh, and as they are rotated, the links 14: will be either drawn inwardly or moved outwardly, depending upon the direction in which the hand lever 17 is turned, this movement of the links causing the toggles to raise or lower the pattern table, 10, as the case may be. In order to automatically lock the toggles in raised position, the apparatus is so arranged that the toggles are moved slightly past center and take against the set screws 21 which are threaded into the end pieces 9, said set screws preventing further outward movement of the toggles. The pattern table is guided during the raising and lowering movement by means of the guide rods or posts 22 which slide in apertures 23 in the end pieces 9, the said guide posts having a ball and socket mounting 24 in the pattern table. The guide posts are of the same construction and serve the same purposes as those described in my co-pending application above set forth. In order to relieve the operating mechanism of a portion of the weight of the pattern table and to maintain the load pressure of the pattern table on the operating mechanism at a more uniform degree, I provide a plurality of counterbalance compression springs 25,

said springs being mounted in the cylinders 26 carried by the frame 7. The pattern table is provided with a plurality of downwardly depending posts 27 which telescope-ywithin the springs 25 and' project withinwthe cylinders 26. By this arrangement, buckling of the springs 25 is prevented. 'The springsare of such weight and length that they are under compression at all times, the degreeof compression of course varying according to the elevation of the pattern table.

10 It will be clear that the mechanism for raising and lowering the "table is simple in character and eflective in operation. "The f act that the segmental gears are also in efiect rock arms' simplifies the mechanism.

The arrangement avoids torsion on the shafts. V I I U Referringnowto the box-like arrangement of the frame work and the pat- .tern table, it will be seen that the operating mechanism is entirely 'inclo'sed and is protected from sand, dirt and'dust which'm'ight ;workpast the pattern table." Directingat- .ten'tion particularly to the end plates 11,

f itl will' be observed thatI have provided a port 28 in eachof said plates, said port-beingadapte'd topermit air to be freely, drawn into the framework. The entrance of sand or .dirt into thesaidvports is prevented by .means of shields '29 'which are secured to 30' ,ithe end plates above said 'ports and. extend downwardly, coveringtheports. On the insteriorfthe end plates lljare provided with jfieigiblafiap. valves 30. preferably composed (of. leather. or other suitable ;1naterial, said valves being .so arranged that as the pattern .table is, moved upwardly,.air is drawn freely into,].,t e framework, and the a table is unloved... downwardly, the flap valves are closedlso that .the. air entrapped within the framework isexpelle'd between the edges of ..the..pattern: table and the sidewalls '8. The Iairl thus expelled carries along with it any ,sand or, dirt which may have been deposited I 'atItheeclg'es-of the 'table.' Asan-addi'tio'nal ;.safeguard-to prevent tl1e .ingress"of sand within the framework, I provide. a lip 31 .on the inside offhej frame 7 beneaththe edges ofthe patterntable. V

a Referring nowtothe means for'lubricat- 1mg the operating .mechanism, it will be .noted thatthe rock shafts15. and 16 are .hollow, the central opening being closed atthe endshby' means of the removableplug's32. The bearings of therock shaftsiinthe bear 55. ing block18at substantially. the central portionof the machine are: lubricatedby means vof the small ports. 33 whichopen from the wch a mber within thexhollow rock shafts, as T will clearly appear on inspection ,of-Fi 1? so. andFig. 2, and thenbearings of'the. rock: shafts in thesides of the frame 7 are lubri-g oated'by similar,.ports.34. Oil is carried. to

1 thebearings for the inner ends vof-the links -.;14e2by-; .-means: of the ports 35 in the rock 35 shafts, and the ducts 36 inthe segmental .which the flask is removed.

. support.

gears. It will thus be apparent that by removing. the plugs 32, the chambers within the rock shafts may be filled with oil and that such oil will lubricate the bearings for the rock shafts as well as the bearings for the links. This method of lubrication is advantageous in that the oil can be supplied from the exterior of the apparatus. The articulated ends of the toggles and links are lubricated by means of the grease cups 37 which are threaded into the toggle pins 38. The toggle pins 38 are provided with a central cavity 39, and external grooves 40 and a port e1 leading from the cavity to the grooves. By turning the grease cups, the lubricant will be forced into the cavity 39 and-out into the grooves 40 to lubricate the toggle joints. Access is had to the grease cups by means of the hand holes 42 provided in the sides of the frames 7.

I The apparatus described is primarily adapted for use in connection with roll ramming apparatus wherein the sand in the flask is'rammed by a rOll which is passed back andforth' over the flask. In operation, the toggles are actuated to raise the table to theposition illustrated in Fig. 2, which movement brings the pattern table together with the pattern it carries into position beineatlrthe lower face of the flask, after ,which the flask isfilled with sand and the "gles are then actuated to lower the table and draw the pattern from the mold, after It has been found in practice that the weight of the ramming roll has a tendency to cause the patterntable-tosprin'g between the points of In order to overcome this difliculty, and at the same time to use a pattern table of the lightest possible weight, I pro- .vide a mechanism adapted to support the pattern table at substantially the central portion thereof, said mechanism being actu atedby' the means for raising and lowering the table. Referring now more particularly to Fig.

..2, it will be seen that I have provided a number of brace arms 43 which are keyed to the rock shafts 15 and 16, preferably two in number; to a shaft, and mounted adjacent the. ends thereof. Mounted in the ends of the brace'arms'are set screws 4L4.- (see Figs.

2 and ,5), said set screws'being adapted to come into engagement with the lower faces 12o ofl the brackets 45 secured to the bottoms .ofjthe longitudinal strengthening ribs l6 formed on thepattern table l0. The arms fl3'are so arranged that they swing into position beneath the brackets-45 when the tog- .gles are inraised position, as will be seen in Fig.2. By' this arrangement, the patthe rock shafts are rotated to lower the pattern table. Adjustment is accomplished by regulation of the set screws 44.

What- I claim is:

1. A sand molding apparatus comprising in combination a movable pattern support, a pair of toggle members for raising and lowering the support, a pair of intermeshing gears, a pivoted link connecting a gear to each toggle member, and means for rotating one of the gear so as to actuate both toggle members.

2. A sand molding apparatus comprising in combination a frame, a movable pattern support mounted therein, a pair of toggle members for raising and lowering the support, a pair of interineshing gears mounted in the frame and intermediate the toggle members, a pivoted link connecting one gear to a toggle member, a pivoted link connecting the other gear to a toggle member, and means for rotating one of the gears.

3. A sand molding apparatus comprising in combination a frame, a movable pattern support mounted therein, a pair of toggle members for raising and lowering the support, a pair of intermeshing gears mounted in the frame and intermediate the toggle members, a link connecting one gear to a toggle member, a link connecting the other gear to a toggle member, and means for rotating one of the gears, said links being connected to the gears on sides opposite the inter-meshing sides of the gears.

4. A sand molding apparatus comprising in combination a frame, a pattern support movably mounted in said frame, a pair of toggles arranged adjacent opposite ends of the support, a pair of rock shafts mounted in the frame intermediate the toggles, a gear on each shaft, said gears intermeshing with one another, a link connecting one gear with a toggle, a link connecting the other gear with the other toggle and means for rotating one of the rock shafts.

A sand molding apparatus comprising the combination of a movable pattern table, mechanism for raising and lowering the table, and means automatically moved to operative position to support the table when the said mechanism is actuated to raise the table to operative position.

6. A sand molding apparatus comprising in combination a movable pattern support, mechanism for raising and lowering the support, and supporting means independent of said mechanism moved into operative position supporting the table when the pattern support is raised to upper position by said mechanism.

7. A sand molding apparatus comprising in combination a movable pattern support, means adjacent the extremities of the support for raising and lowering the support,

and means intermediate said raising and lowering means automatically moved to operative position supporting the table when the table is raised to upper position.

8. A sand molding apparatus comprising in combination a movable pattern support, a toggle adjacent each end of the support for raising and lowering it, power means for actuating the toggles, and supporting means intermediate the toggles adapted to support the pattern support, said means being moved to supporting position by the power means when the pattern support is raised.

9. A sand molding apparatus comprising in combination a movable pattern support, a toggle adjacent each end of the support for raising and lowering it, a rotary shaft, a connection between the shaft and the toggles and a brace member mounted on said shaft and adapted to be moved to operative position supporting the pattern support when the shaft is rotated to raise the support.

10. A sand molding apparatus comprising in combination a closed frame, a pattern supporting table movably mounted in said frame, mechanism mounted within the frame for raising and'lowering the table, said frame being provided with a port, and a valvular device controlling said port, said device permitting air to flow into the frame when the table is being raised and closing when the table is being lowered.

11. A sand molding apparatus comprising in combination a frame, a movable pattern table mounted in the frame, said frame and table constituting a closed box, mechanism within said box for raising and lowering the table, the said frame having a port adapted to permit air to flow into the box, and a valvular device controlling said port and adapted to close said port when the 'table is being lowered.

12. A sand molding apparatus comprising in combination a frame open at the top, a pattern supporting table slidably mounted in said frame and closing the top thereof, means within the frame for raising and lowering the table, a plate carried on the table and overlapping a side of the frame, said plate being provided with an opening, and a flap valve controlling said opening and adapted to permit air to flow through said opening into the frame when the table is being raised and closing said opening when the table is being lowered.

13. A sand molding apparatus comprising in combination a closed frame, a pattern supporting table movably mounted in said frame, said frame and table constituting in effect a closed box, mechanism within the frame for raising and lowering the table, and valvular means admitting air Within the frame when the table is being raised and closing when the table is being lowered.

14:. A sand molding apparatus comprising in combination a frame open at the top,

5 a movable pattern supporting table mounted in the frame for Vertical movement and constituting With the frame a closed box,

means for raising and lowering the table,

and valvular meanswhereby air is admit- 10 ted into the frame below the table when the latter is being raised and the air cut oil when the table is being moved downward.

In testimony whereof I have hereunto signed my name in the presence of the two subscribed witnesses.

V HARRY P. MACDONALD.

Witnesses: I i

J. V. ARN LD, C. C. GREENLEE.

Copies 0! this patent may' be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. Q. 

